;;; help.el --- help commands for Emacs
-;; Copyright (C) 1985, 1986, 1993, 1994, 1998 Free Software Foundation, Inc.
+;; Copyright (C) 1985, 1986, 1993, 1994, 1998, 1999, 2000, 2001
+;; Free Software Foundation, Inc.
;; Maintainer: FSF
;; Keywords: help, internal
;;; Commentary:
;; This code implements GNU Emacs' on-line help system, the one invoked by
-;;`M-x help-for-help'.
+;; `M-x help-for-help'.
;;; Code:
;; or run interpreted, but not when the compiled code is loaded.
(eval-when-compile (require 'help-macro))
+;; This makes `with-output-to-temp-buffer' buffers use `help-mode'.
+(add-hook 'temp-buffer-setup-hook 'help-mode-setup)
+(add-hook 'temp-buffer-show-hook 'help-mode-finish)
+
(defvar help-map (make-sparse-keymap)
"Keymap for characters following the Help key.")
-(defvar help-mode-map (make-sparse-keymap)
- "Keymap for help mode.")
-
(define-key global-map (char-to-string help-char) 'help-command)
(define-key global-map [help] 'help-command)
(define-key global-map [f1] 'help-command)
(define-key help-map "l" 'view-lossage)
(define-key help-map "m" 'describe-mode)
+(define-key help-map "\C-m" 'view-order-manuals)
(define-key help-map "\C-n" 'view-emacs-news)
(define-key help-map "n" 'view-emacs-news)
(autoload 'finder-by-keyword "finder"
"Find packages matching a given keyword." t)
+(define-key help-map "P" 'view-emacs-problems)
+
(define-key help-map "s" 'describe-syntax)
(define-key help-map "t" 'help-with-tutorial)
(define-key help-map "q" 'help-quit)
-(define-key help-mode-map [mouse-2] 'help-follow-mouse)
-(define-key help-mode-map "\C-c\C-b" 'help-go-back)
-(define-key help-mode-map "\C-c\C-c" 'help-follow)
-(define-key help-mode-map "\t" 'help-next-ref)
-(define-key help-mode-map [backtab] 'help-previous-ref)
-(define-key help-mode-map [(shift tab)] 'help-previous-ref)
-;; Documentation only, since we use minor-mode-overriding-map-alist.
-(define-key help-mode-map "\r" 'help-follow)
-
-;; Font-locking is incompatible with the new xref stuff.
-;(defvar help-font-lock-keywords
-; (eval-when-compile
-; (let ((name-char "[-+a-zA-Z0-9_*]") (sym-char "[-+a-zA-Z0-9_:*]"))
-; (list
-; ;;
-; ;; The symbol itself.
-; (list (concat "\\`\\(" name-char "+\\)\\(\\(:\\)\\|\\('\\)\\)")
-; '(1 (if (match-beginning 3)
-; font-lock-function-name-face
-; font-lock-variable-name-face)))
-; ;;
-; ;; Words inside `' which tend to be symbol names.
-; (list (concat "`\\(" sym-char sym-char "+\\)'")
-; 1 'font-lock-constant-face t)
-; ;;
-; ;; CLisp `:' keywords as references.
-; (list (concat "\\<:" sym-char "+\\>") 0 'font-lock-builtin-face t))))
-; "Default expressions to highlight in Help mode.")
-
-(defvar help-xref-stack nil
- "A stack of ways by which to return to help buffers after following xrefs.
-Used by `help-follow' and `help-xref-go-back'.
-An element looks like (POSITION FUNCTION ARGS...).
-To use the element, do (apply FUNCTION ARGS) then (goto-char POSITION).")
-(put 'help-xref-stack 'permanent-local t)
-
-(defvar help-xref-stack-item nil
- "An item for `help-follow' in this buffer to push onto `help-xref-stack'.
-The format is (FUNCTION ARGS...).")
-(put 'help-xref-stack-item 'permanent-local t)
-
-(setq-default help-xref-stack nil help-xref-stack-item nil)
-
-(defun help-mode ()
- "Major mode for viewing help text and navigating references in it.
-Entry to this mode runs the normal hook `help-mode-hook'.
-Commands:
-\\{help-mode-map}"
- (interactive)
- (kill-all-local-variables)
- (use-local-map help-mode-map)
- (setq mode-name "Help")
- (setq major-mode 'help-mode)
- (make-local-variable 'font-lock-defaults)
- (setq font-lock-defaults nil) ; font-lock would defeat xref
- (view-mode)
- (make-local-variable 'view-no-disable-on-exit)
- (setq view-no-disable-on-exit t)
- ;; `help-make-xrefs' would be run here if not invoked from
- ;; `help-mode-maybe'.
- (run-hooks 'help-mode-hook))
-
-(defun help-mode-setup ()
- (help-mode)
- (setq buffer-read-only nil))
-
-(add-hook 'temp-buffer-setup-hook 'help-mode-setup)
-
-(defun help-mode-finish ()
- (when (eq major-mode 'help-mode)
- ;; View mode's read-only status of existing *Help* buffer is lost
- ;; by with-output-to-temp-buffer.
- (toggle-read-only 1)
- (help-make-xrefs (current-buffer)))
- (setq view-return-to-alist
- (list (cons (selected-window) help-return-method))))
-
-(add-hook 'temp-buffer-show-hook 'help-mode-finish)
-
+\f
(defun help-quit ()
"Just exit from the Help command's command loop."
(interactive)
nil)
-(defun help-with-tutorial (&optional arg)
- "Select the Emacs learn-by-doing tutorial.
-If there is a tutorial version written in the language
-of the selected language environment, that version is used.
-If there's no tutorial in that language, `TUTORIAL' is selected.
-With arg, you are asked to choose which language."
- (interactive "P")
- (let ((lang (if arg
- (read-language-name 'tutorial "Language: " "English")
- (if (get-language-info current-language-environment 'tutorial)
- current-language-environment
- "English")))
- file filename)
- (setq filename (get-language-info lang 'tutorial))
- (setq file (expand-file-name (concat "~/" filename)))
- (delete-other-windows)
- (if (get-file-buffer file)
- (switch-to-buffer (get-file-buffer file))
- (switch-to-buffer (create-file-buffer file))
- (setq buffer-file-name file)
- (setq default-directory (expand-file-name "~/"))
- (setq buffer-auto-save-file-name nil)
- (insert-file-contents (expand-file-name filename data-directory))
- (goto-char (point-min))
- (search-forward "\n<<")
- (beginning-of-line)
- (delete-region (point) (progn (end-of-line) (point)))
- (let ((n (- (window-height (selected-window))
- (count-lines (point-min) (point))
- 6)))
- (if (< n 12)
- (newline n)
- ;; Some people get confused by the large gap.
- (newline (/ n 2))
- (insert "[Middle of page left blank for didactic purposes. "
- "Text continues below]")
- (newline (- n (/ n 2)))))
- (goto-char (point-min))
- (set-buffer-modified-p nil))))
-
-(defun describe-key-briefly (key &optional insert)
- "Print the name of the function KEY invokes. KEY is a string.
-If INSERT (the prefix arg) is non-nil, insert the message in the buffer."
- (interactive "kDescribe key briefly: \nP")
- (save-excursion
- (let ((modifiers (event-modifiers (aref key 0)))
- (standard-output (if insert (current-buffer) t))
- window position)
- ;; For a mouse button event, go to the button it applies to
- ;; to get the right key bindings. And go to the right place
- ;; in case the keymap depends on where you clicked.
- (if (or (memq 'click modifiers) (memq 'down modifiers)
- (memq 'drag modifiers))
- (setq window (posn-window (event-start (aref key 0)))
- position (posn-point (event-start (aref key 0)))))
- (if (windowp window)
- (progn
- (set-buffer (window-buffer window))
- (goto-char position)))
- ;; Ok, now look up the key and name the command.
- (let ((defn (key-binding key))
- (key-desc (key-description key)))
- (if (or (null defn) (integerp defn))
- (princ (format "%s is undefined" key-desc))
- (princ (format (if insert
- "`%s' (`%s')"
- (if (windowp window)
- "%s at that spot runs the command %s"
- "%s runs the command %s"))
- key-desc
- (if (symbolp defn) defn (prin1-to-string defn)))))))))
-
(defvar help-return-method nil
"What to do to \"exit\" the help buffer.
This is a list
;; Secondly, the buffer has not been displayed yet,
;; so we don't know whether its frame will be selected.
nil)
+ (display-buffer-reuse-frames
+ (setq help-return-method (cons (selected-window)
+ 'quit-window))
+ nil)
((not (one-window-p t))
(setq help-return-method
(cons (selected-window) 'quit-window))
(funcall (or function 'message)
(concat
(if first-message
- (substitute-command-keys first-message)
- "")
- (if first-message " " "")
+ (substitute-command-keys first-message))
+ (if first-message " ")
;; If the help buffer will go in a separate frame,
;; it's no use mentioning a command to scroll, so don't.
(if (special-display-p (buffer-name standard-output))
(substitute-command-keys
"\\[scroll-other-window] to scroll the help."))))))))
-(defun describe-key (key)
- "Display documentation of the function invoked by KEY. KEY is a string."
- (interactive "kDescribe key: ")
- (save-excursion
- (let ((modifiers (event-modifiers (aref key 0)))
- window position)
- ;; For a mouse button event, go to the button it applies to
- ;; to get the right key bindings. And go to the right place
- ;; in case the keymap depends on where you clicked.
- (if (or (memq 'click modifiers) (memq 'down modifiers)
- (memq 'drag modifiers))
- (setq window (posn-window (event-start (aref key 0)))
- position (posn-point (event-start (aref key 0)))))
- (if (windowp window)
- (progn
- (set-buffer (window-buffer window))
- (goto-char position)))
- (let ((defn (key-binding key)))
- (if (or (null defn) (integerp defn))
- (message "%s is undefined" (key-description key))
- (with-output-to-temp-buffer "*Help*"
- (princ (key-description key))
- (if (windowp window)
- (princ " at that spot"))
- (princ " runs the command ")
- (prin1 defn)
- (princ "\n which is ")
- (describe-function-1 defn nil)
- (print-help-return-message)))))))
+;; So keyboard macro definitions are documented correctly
+(fset 'defining-kbd-macro (symbol-function 'start-kbd-macro))
-(defun describe-mode ()
- "Display documentation of current major mode and minor modes.
-The major mode description comes first, followed by the minor modes,
-each on a separate page.
+(defalias 'help 'help-for-help)
+(make-help-screen help-for-help
+ "a b c C f F C-f i I k C-k l L m n p s t v w C-c C-d C-n C-p C-w; ? for help:"
+ "You have typed %THIS-KEY%, the help character. Type a Help option:
+\(Use SPC or DEL to scroll through this text. Type \\<help-map>\\[help-quit] to exit the Help command.)
-For this to work correctly for a minor mode, the mode's indicator variable
-\(listed in `minor-mode-alist') must also be a function whose documentation
-describes the minor mode."
- (interactive)
- (with-output-to-temp-buffer "*Help*"
- (when minor-mode-alist
- (princ "The major mode is described first.
-For minor modes, see following pages.\n\n"))
- (princ mode-name)
- (princ " mode:\n")
- (princ (documentation major-mode))
- (help-setup-xref (list #'help-xref-mode (current-buffer)) (interactive-p))
- (let ((minor-modes minor-mode-alist))
- (while minor-modes
- (let* ((minor-mode (car (car minor-modes)))
- (indicator (car (cdr (car minor-modes)))))
- ;; Document a minor mode if it is listed in minor-mode-alist,
- ;; bound locally in this buffer, non-nil, and has a function
- ;; definition.
- (if (and (symbol-value minor-mode)
- (fboundp minor-mode))
- (let ((pretty-minor-mode minor-mode))
- (if (string-match "-mode$" (symbol-name minor-mode))
- (setq pretty-minor-mode
- (capitalize
- (substring (symbol-name minor-mode)
- 0 (match-beginning 0)))))
- (while (and indicator (symbolp indicator)
- (boundp indicator)
- (not (eq indicator (symbol-value indicator))))
- (setq indicator (symbol-value indicator)))
- (princ "\n\f\n")
- (princ (format "%s minor mode (%s):\n"
- pretty-minor-mode
- (if indicator
- (format "indicator%s" indicator)
- "no indicator")))
- (princ (documentation minor-mode)))))
- (setq minor-modes (cdr minor-modes))))
- (print-help-return-message)))
+a command-apropos. Give a substring, and see a list of commands
+ (functions interactively callable) that contain
+ that substring. See also the apropos command.
+b describe-bindings. Display table of all key bindings.
+c describe-key-briefly. Type a command key sequence;
+ it prints the function name that sequence runs.
+C describe-coding-system. This describes either a specific coding system
+ (if you type its name) or the coding systems currently in use
+ (if you type just RET).
+f describe-function. Type a function name and get documentation of it.
+C-f Info-goto-emacs-command-node. Type a function name;
+ it takes you to the Info node for that command.
+i info. The info documentation reader.
+I describe-input-method. Describe a specific input method (if you type
+ its name) or the current input method (if you type just RET).
+C-i info-lookup-symbol. Display the definition of a specific symbol
+ as found in the manual for the language this buffer is written in.
+k describe-key. Type a command key sequence;
+ it displays the full documentation.
+C-k Info-goto-emacs-key-command-node. Type a command key sequence;
+ it takes you to the Info node for the command bound to that key.
+l view-lossage. Show last 100 characters you typed.
+L describe-language-environment. This describes either a
+ specific language environment (if you type its name)
+ or the current language environment (if you type just RET).
+m describe-mode. Print documentation of current minor modes,
+ and the current major mode, including their special commands.
+n view-emacs-news. Display news of recent Emacs changes.
+p finder-by-keyword. Find packages matching a given topic keyword.
+s describe-syntax. Display contents of syntax table, plus explanations.
+t help-with-tutorial. Select the Emacs learn-by-doing tutorial.
+v describe-variable. Type name of a variable;
+ it displays the variable's documentation and value.
+w where-is. Type command name; it prints which keystrokes
+ invoke that command.
-;; So keyboard macro definitions are documented correctly
-(fset 'defining-kbd-macro (symbol-function 'start-kbd-macro))
+F Display the frequently asked questions file.
+h Display the HELLO file which illustrates various scripts.
+C-c Display Emacs copying permission (General Public License).
+C-d Display Emacs ordering information.
+C-n Display news of recent Emacs changes.
+C-p Display information about the GNU project.
+C-w Display information on absence of warranty for GNU Emacs."
+ help-map)
+
+\f
+
+(defun function-called-at-point ()
+ "Return a function around point or else called by the list containing point.
+If that doesn't give a function, return nil."
+ (with-syntax-table emacs-lisp-mode-syntax-table
+ (or (condition-case ()
+ (save-excursion
+ (or (not (zerop (skip-syntax-backward "_w")))
+ (eq (char-syntax (following-char)) ?w)
+ (eq (char-syntax (following-char)) ?_)
+ (forward-sexp -1))
+ (skip-chars-forward "'")
+ (let ((obj (read (current-buffer))))
+ (and (symbolp obj) (fboundp obj) obj)))
+ (error nil))
+ (condition-case ()
+ (save-excursion
+ (save-restriction
+ (narrow-to-region (max (point-min)
+ (- (point) 1000)) (point-max))
+ ;; Move up to surrounding paren, then after the open.
+ (backward-up-list 1)
+ (forward-char 1)
+ ;; If there is space here, this is probably something
+ ;; other than a real Lisp function call, so ignore it.
+ (if (looking-at "[ \t]")
+ (error "Probably not a Lisp function call"))
+ (let ((obj (read (current-buffer))))
+ (and (symbolp obj) (fboundp obj) obj))))
+ (error nil)))))
+
+\f
+;;; `User' help functions
(defun describe-distribution ()
"Display info on how to obtain the latest version of GNU Emacs."
"Display info on the GNU project."
(interactive)
(find-file-read-only
- (expand-file-name "GNU" data-directory))
+ (expand-file-name "THE-GNU-PROJECT" data-directory))
(goto-char (point-min)))
(defun describe-no-warranty ()
(aset prefix i (aref key i))
(setq i (1+ i)))
prefix)))))
-;; Make C-h after a prefix, when not specifically bound,
+;; Make C-h after a prefix, when not specifically bound,
;; run describe-prefix-bindings.
(setq prefix-help-command 'describe-prefix-bindings)
(defun view-emacs-news (&optional arg)
"Display info on recent changes to Emacs.
-With numeric argument display information on correspondingly older changes."
+With numeric argument, display information on correspondingly older changes."
(interactive "P")
- (let* ((arg (if arg (prefix-numeric-value arg) 0)))
- (find-file-read-only
- (expand-file-name (concat (make-string arg ?O) "NEWS")
- data-directory))))
+ (let* ((arg (if arg (prefix-numeric-value arg) 0))
+ (file (cond ((eq arg 0) "NEWS")
+ ((eq arg 1) "ONEWS")
+ (t
+ (nth (- arg 2)
+ (nreverse (directory-files data-directory
+ nil "^ONEWS\\.[0-9]+$"
+ nil)))))))
+ (if file
+ (find-file-read-only (expand-file-name file data-directory))
+ (error "No such old news"))))
+
+(defun view-order-manuals ()
+ "Display the Emacs ORDERS file."
+ (interactive)
+ (find-file-read-only (expand-file-name "ORDERS" data-directory))
+ (goto-address))
(defun view-emacs-FAQ ()
"Display the Emacs Frequently Asked Questions (FAQ) file."
(interactive)
- (find-file-read-only (expand-file-name "FAQ" data-directory)))
+ ;; (find-file-read-only (expand-file-name "FAQ" data-directory))
+ (info "(efaq)"))
+
+(defun view-emacs-problems ()
+ "Display info on known problems with Emacs and possible workarounds."
+ (interactive)
+ (view-file (expand-file-name "PROBLEMS" data-directory)))
(defun view-lossage ()
- "Display last 100 input keystrokes."
+ "Display last 100 input keystrokes.
+
+To record all your input on a file, use `open-dribble-file'."
(interactive)
- (with-output-to-temp-buffer "*Help*"
+ (help-setup-xref (list #'view-lossage) (interactive-p))
+ (with-output-to-temp-buffer (help-buffer)
(princ (mapconcat (function (lambda (key)
(if (or (integerp key)
(symbolp key)
(prin1-to-string key nil))))
(recent-keys)
" "))
- (save-excursion
- (set-buffer standard-output)
+ (with-current-buffer standard-output
(goto-char (point-min))
(while (progn (move-to-column 50) (not (eobp)))
(search-forward " " nil t)
- (insert "\n"))
- (setq help-xref-stack nil
- help-xref-stack-item nil))
+ (insert "\n")))
(print-help-return-message)))
-(defalias 'help 'help-for-help)
-(make-help-screen help-for-help
- "a b c C f F C-f i I k C-k l L m n p s t v w C-c C-d C-n C-p C-w; ? for help:"
- "You have typed %THIS-KEY%, the help character. Type a Help option:
-\(Use SPC or DEL to scroll through this text. Type \\<help-map>\\[help-quit] to exit the Help command.)
-
-a command-apropos. Give a substring, and see a list of commands
- (functions interactively callable) that contain
- that substring. See also the apropos command.
-b describe-bindings. Display table of all key bindings.
-c describe-key-briefly. Type a command key sequence;
- it prints the function name that sequence runs.
-C describe-coding-system. This describes either a specific coding system
- (if you type its name) or the coding systems currently in use
- (if you type just RET).
-f describe-function. Type a function name and get documentation of it.
-C-f Info-goto-emacs-command-node. Type a function name;
- it takes you to the Info node for that command.
-i info. The info documentation reader.
-I describe-input-method. Describe a specific input method (if you type
- its name) or the current input method (if you type just RET).
-k describe-key. Type a command key sequence;
- it displays the full documentation.
-C-k Info-goto-emacs-key-command-node. Type a command key sequence;
- it takes you to the Info node for the command bound to that key.
-l view-lossage. Shows last 100 characters you typed.
-L describe-language-environment. This describes either the a
- specific language environment (if you type its name)
- or the current language environment (if you type just RET).
-m describe-mode. Print documentation of current minor modes,
- and the current major mode, including their special commands.
-n view-emacs-news. Shows emacs news file.
-p finder-by-keyword. Find packages matching a given topic keyword.
-s describe-syntax. Display contents of syntax table, plus explanations
-t help-with-tutorial. Select the Emacs learn-by-doing tutorial.
-v describe-variable. Type name of a variable;
- it displays the variable's documentation and value.
-w where-is. Type command name; it prints which keystrokes
- invoke that command.
-
-F Display the frequently asked questions file.
-h Display the HELLO file which illustrates various scripts.
-C-c Display Emacs copying permission (General Public License).
-C-d Display Emacs ordering information.
-C-n Display news of recent Emacs changes.
-C-p Display information about the GNU project.
-C-w Display information on absence of warranty for GNU Emacs."
- help-map)
-
-;; Return a function whose name is around point.
-;; If that gives no function, return a function which is called by the
-;; list containing point.
-;; If that doesn't give a function, return nil.
-(defun function-called-at-point ()
- (let ((stab (syntax-table)))
- (set-syntax-table emacs-lisp-mode-syntax-table)
- (unwind-protect
- (or (condition-case ()
- (save-excursion
- (or (not (zerop (skip-syntax-backward "_w")))
- (eq (char-syntax (following-char)) ?w)
- (eq (char-syntax (following-char)) ?_)
- (forward-sexp -1))
- (skip-chars-forward "'")
- (let ((obj (read (current-buffer))))
- (and (symbolp obj) (fboundp obj) obj)))
- (error nil))
- (condition-case ()
- (save-excursion
- (save-restriction
- (narrow-to-region (max (point-min) (- (point) 1000)) (point-max))
- ;; Move up to surrounding paren, then after the open.
- (backward-up-list 1)
- (forward-char 1)
- ;; If there is space here, this is probably something
- ;; other than a real Lisp function call, so ignore it.
- (if (looking-at "[ \t]")
- (error "Probably not a Lisp function call"))
- (let (obj)
- (setq obj (read (current-buffer)))
- (and (symbolp obj) (fboundp obj) obj))))
- (error nil)))
- (set-syntax-table stab))))
-
-(defvar symbol-file-load-history-loaded nil
- "Non-nil means we have loaded the file `fns-VERSION.el' in `exec-directory'.
-That file records the part of `load-history' for preloaded files,
-which is cleared out before dumping to make Emacs smaller.")
-
-(defun symbol-file (function)
- "Return the input source from which SYM was loaded.
-The value is normally a string that was passed to `load':
-either an absolute file name, or a library name
-\(with no directory name and no `.el' or `.elc' at the end).
-It can also be nil, if the definition is not associated with any file."
- (unless symbol-file-load-history-loaded
- (load (expand-file-name
- ;; fns-XX.YY.ZZ.el does not work on DOS filesystem.
- (if (eq system-type 'ms-dos)
- "fns.el"
- (format "fns-%s.el" emacs-version))
- exec-directory)
- ;; The file name fns-%s.el already has a .el extension.
- nil nil t)
- (setq symbol-file-load-history-loaded t))
- (let ((files load-history)
- file functions)
- (while files
- (if (memq function (cdr (car files)))
- (setq file (car (car files)) files nil))
- (setq files (cdr files)))
- file))
-
-(defun describe-function (function)
- "Display the full documentation of FUNCTION (a symbol)."
- (interactive
- (let ((fn (function-called-at-point))
- (enable-recursive-minibuffers t)
- val)
- (setq val (completing-read (if fn
- (format "Describe function (default %s): " fn)
- "Describe function: ")
- obarray 'fboundp t nil nil (symbol-name fn)))
- (list (if (equal val "")
- fn (intern val)))))
- (if function
- (with-output-to-temp-buffer "*Help*"
- (prin1 function)
- ;; Use " is " instead of a colon so that
- ;; it is easier to get out the function name using forward-sexp.
- (princ " is ")
- (describe-function-1 function nil)
- (print-help-return-message)
- (save-excursion
- (set-buffer standard-output)
- ;; Return the text we displayed.
- (buffer-string)))
- (message "You didn't specify a function")))
-
-(defun describe-function-1 (function parens)
- (let* ((def (symbol-function function))
- file-name string need-close
- (beg (if (commandp def) "an interactive " "a ")))
- (setq string
- (cond ((or (stringp def)
- (vectorp def))
- "a keyboard macro")
- ((subrp def)
- (concat beg "built-in function"))
- ((byte-code-function-p def)
- (concat beg "compiled Lisp function"))
- ((symbolp def)
- (while (symbolp (symbol-function def))
- (setq def (symbol-function def)))
- (format "an alias for `%s'" def))
- ((eq (car-safe def) 'lambda)
- (concat beg "Lisp function"))
- ((eq (car-safe def) 'macro)
- "a Lisp macro")
- ((eq (car-safe def) 'mocklisp)
- "a mocklisp function")
- ((eq (car-safe def) 'autoload)
- (setq file-name (nth 1 def))
- (format "%s autoloaded %s"
- (if (commandp def) "an interactive" "an")
- (if (eq (nth 4 def) 'keymap) "keymap"
- (if (nth 4 def) "Lisp macro" "Lisp function"))
- ))
- (t "")))
- (when (and parens (not (equal string "")))
- (setq need-close t)
- (princ "("))
- (princ string)
- (or file-name
- (setq file-name (symbol-file function)))
- (if file-name
- (progn
- (princ " in `")
- ;; We used to add .el to the file name,
- ;; but that's completely wrong when the user used load-file.
- (princ file-name)
- (princ "'")
- ;; Make a hyperlink to the library.
- (with-current-buffer "*Help*"
- (save-excursion
- (re-search-backward "`\\([^`']+\\)'" nil t)
- (help-xref-button 1 #'(lambda (arg)
- (let ((location
- (find-function-noselect arg)))
- (pop-to-buffer (car location))
- (goto-char (cdr location))))
- function)))))
- (if need-close (princ ")"))
- (princ ".")
- (terpri)
- ;; Handle symbols aliased to other symbols.
- (setq def (indirect-function def))
- ;; If definition is a macro, find the function inside it.
- (if (eq (car-safe def) 'macro)
- (setq def (cdr def)))
- (let ((arglist (cond ((byte-code-function-p def)
- (car (append def nil)))
- ((eq (car-safe def) 'lambda)
- (nth 1 def))
- (t t))))
- (if (listp arglist)
- (progn
- (princ (cons function
- (mapcar (lambda (arg)
- (if (memq arg '(&optional &rest))
- arg
- (intern (upcase (symbol-name arg)))))
- arglist)))
- (terpri))))
- (let ((doc (documentation function)))
- (if doc
- (progn (terpri)
- (princ doc)
- (help-setup-xref (list #'describe-function function) (interactive-p)))
- (princ "not documented")))))
-
-;; We return 0 if we can't find a variable to return.
-(defun variable-at-point ()
- (condition-case ()
- (let ((stab (syntax-table)))
- (unwind-protect
- (save-excursion
- (set-syntax-table emacs-lisp-mode-syntax-table)
- (or (not (zerop (skip-syntax-backward "_w")))
- (eq (char-syntax (following-char)) ?w)
- (eq (char-syntax (following-char)) ?_)
- (forward-sexp -1))
- (skip-chars-forward "'")
- (let ((obj (read (current-buffer))))
- (or (and (symbolp obj) (boundp obj) obj)
- 0)))
- (set-syntax-table stab)))
- (error 0)))
-
-(defun describe-variable (variable)
- "Display the full documentation of VARIABLE (a symbol).
-Returns the documentation as a string, also."
- (interactive
- (let ((v (variable-at-point))
- (enable-recursive-minibuffers t)
- val)
- (setq val (completing-read (if (symbolp v)
- (format "Describe variable (default %s): " v)
- "Describe variable: ")
- obarray 'boundp t nil nil
- (if (symbolp v) (symbol-name v))))
- (list (if (equal val "")
- v (intern val)))))
- (if (symbolp variable)
- (let (valvoid)
- (with-output-to-temp-buffer "*Help*"
- (prin1 variable)
- (if (not (boundp variable))
- (progn
- (princ " is void")
- (terpri)
- (setq valvoid t))
- (princ "'s value is ")
- (terpri)
- (pp (symbol-value variable))
- (terpri))
- (if (local-variable-p variable)
- (progn
- (princ (format "Local in buffer %s; " (buffer-name)))
- (if (not (default-boundp variable))
- (princ "globally void")
- (princ "global value is ")
- (terpri)
- (pp (default-value variable)))
- (terpri)))
- (terpri)
- (save-current-buffer
- (set-buffer standard-output)
- (if (> (count-lines (point-min) (point-max)) 10)
- (progn
- (goto-char (point-min))
- (if valvoid
- (forward-line 1)
- (forward-sexp 1)
- (delete-region (point) (progn (end-of-line) (point)))
- (insert "'s value is shown below.\n\n")
- (save-excursion
- (insert "\n\nValue:"))))))
- (princ "Documentation:")
- (terpri)
- (let ((doc (documentation-property variable 'variable-documentation)))
- (princ (or doc "not documented as a variable.")))
- (help-setup-xref (list #'describe-variable variable) (interactive-p))
-
- ;; Make a link to customize if this variable can be customized.
- ;; Note, it is not reliable to test only for a custom-type property
- ;; because those are only present after the var's definition
- ;; has been loaded.
- (if (or (user-variable-p variable) (get variable 'custom-type))
- (let ((customize-label "customize"))
- (terpri)
- (terpri)
- (princ (concat "You can " customize-label " this variable."))
- (with-current-buffer "*Help*"
- (save-excursion
- (re-search-backward
- (concat "\\(" customize-label "\\)") nil t)
- (help-xref-button 1 #'(lambda (v)
- (customize-variable v)) variable)
- ))))
- ;; Make a hyperlink to the library if appropriate. (Don't
- ;; change the format of the buffer's initial line in case
- ;; anything expects the current format.)
- (let ((file-name (symbol-file variable)))
- (when file-name
- (princ "\n\nDefined in `")
- (princ file-name)
- (princ "'.")
- (with-current-buffer "*Help*"
- (save-excursion
- (re-search-backward "`\\([^`']+\\)'" nil t)
- (help-xref-button 1 (lambda (arg)
- (let ((location
- (find-variable-noselect arg)))
- (pop-to-buffer (car location))
- (goto-char (cdr location))))
- variable)))))
-
- (print-help-return-message)
- (save-excursion
- (set-buffer standard-output)
- ;; Return the text we displayed.
- (buffer-string))))
- (message "You did not specify a variable")))
+\f
+;; Key bindings
(defun describe-bindings (&optional prefix buffer)
"Show a list of all defined keys, and their definitions.
then we display only bindings that start with that prefix.
The optional argument BUFFER specifies which buffer's bindings
to display (default, the current buffer)."
- (interactive "P")
+ (interactive)
(or buffer (setq buffer (current-buffer)))
+ (help-setup-xref (list #'describe-bindings prefix buffer) (interactive-p))
(with-current-buffer buffer
- (describe-bindings-internal nil prefix))
- (with-current-buffer "*Help*"
- (help-setup-xref (list #'describe-bindings prefix buffer)
- (interactive-p))))
+ (describe-bindings-internal nil prefix)))
+
+;; This function used to be in keymap.c.
+(defun describe-bindings-internal (&optional menus prefix)
+ "Show a list of all defined keys, and their definitions.
+We put that list in a buffer, and display the buffer.
+
+The optional argument MENUS, if non-nil, says to mention menu bindings.
+\(Ordinarily these are omitted from the output.)
+The optional argument PREFIX, if non-nil, should be a key sequence;
+then we display only bindings that start with that prefix."
+ (interactive)
+ (let ((buf (current-buffer)))
+ (with-output-to-temp-buffer "*Help*"
+ (with-current-buffer standard-output
+ (describe-buffer-bindings buf prefix menus)))))
(defun where-is (definition &optional insert)
- "Print message listing key sequences that invoke specified command.
+ "Print message listing key sequences that invoke the command DEFINITION.
Argument is a command definition, usually a symbol with a function definition.
If INSERT (the prefix arg) is non-nil, insert the message in the buffer."
(interactive
(let ((fn (function-called-at-point))
- (enable-recursive-minibuffers t)
+ (enable-recursive-minibuffers t)
val)
(setq val (completing-read (if fn
(format "Where is command (default %s): " fn)
"Where is command: ")
- obarray 'fboundp t))
+ obarray 'commandp t))
(list (if (equal val "")
fn (intern val))
current-prefix-arg)))
(princ (format "%s is not on any key" definition)))))
nil)
-(defun locate-library (library &optional nosuffix path interactive-call)
- "Show the precise file name of Emacs library LIBRARY.
-This command searches the directories in `load-path' like `M-x load-library'
-to find the file that `M-x load-library RET LIBRARY RET' would load.
-Optional second arg NOSUFFIX non-nil means don't add suffixes `.elc' or `.el'
-to the specified name LIBRARY.
-
-If the optional third arg PATH is specified, that list of directories
-is used instead of `load-path'."
- (interactive (list (read-string "Locate library: ")
- nil nil
- t))
- (let (result)
- (catch 'answer
- (mapcar
- (lambda (dir)
- (mapcar
- (lambda (suf)
- (let ((try (expand-file-name (concat library suf) dir)))
- (and (file-readable-p try)
- (null (file-directory-p try))
- (progn
- (setq result try)
- (throw 'answer try)))))
- (if nosuffix
- '("")
- '(".elc" ".el" "")
-;;; load doesn't handle this yet.
-;;; (let ((basic '(".elc" ".el" ""))
-;;; (compressed '(".Z" ".gz" "")))
-;;; ;; If autocompression mode is on,
-;;; ;; consider all combinations of library suffixes
-;;; ;; and compression suffixes.
-;;; (if (rassq 'jka-compr-handler file-name-handler-alist)
-;;; (apply 'nconc
-;;; (mapcar (lambda (compelt)
-;;; (mapcar (lambda (baselt)
-;;; (concat baselt compelt))
-;;; basic))
-;;; compressed))
-;;; basic))
- )))
- (or path load-path)))
- (and interactive-call
- (if result
- (message "Library is file %s" result)
- (message "No library %s in search path" library)))
- result))
+(defun string-key-binding (key)
+ "Value is the binding of KEY in a string.
+If KEY is an event on a string, and that string has a `local-map'
+or `keymap' property, return the binding of KEY in the string's keymap."
+ (let* ((defn nil)
+ (start (when (vectorp key)
+ (if (memq (aref key 0) '(mode-line header-line))
+ (event-start (aref key 1))
+ (and (consp (aref key 0))
+ (event-start (aref key 0))))))
+ (string-info (and (consp start) (nth 4 start))))
+ (when string-info
+ (let* ((string (car string-info))
+ (pos (cdr string-info))
+ (local-map (and (> pos 0)
+ (< pos (length string))
+ (or (get-text-property pos 'local-map string)
+ (get-text-property pos 'keymap string)))))
+ (setq defn (and local-map (lookup-key local-map key)))))
+ defn))
-\f
-;;; Grokking cross-reference information in doc strings and
-;;; hyperlinking it.
-
-;; This may have some scope for extension and the same or something
-;; similar should be done for widget doc strings, which currently use
-;; another mechanism.
-
-(defcustom help-highlight-p t
- "*If non-nil, `help-make-xrefs' highlight cross-references.
-Under a window system it highlights them with face defined by
-`help-highlight-face'. On a character terminal highlighted
-references look like cross-references in info mode."
- :group 'help
- :version "20.3"
- :type 'boolean)
-
-(defcustom help-highlight-face 'underline
- "Face used by `help-make-xrefs' to highlight cross-references.
-Must be previously-defined."
- :group 'help
- :version "20.3"
- :type 'face)
-
-(defvar help-back-label "[back]"
- "Label to use by `help-make-xrefs' for the go-back reference.")
-
-(defvar help-xref-symbol-regexp
- (concat "\\(\\<\\(\\(variable\\|option\\)\\|"
- "\\(function\\|command\\)\\|"
- "\\(symbol\\)\\)\\s-+\\)?"
- ;; Note starting with word-syntax character:
- "`\\(\\sw\\(\\sw\\|\\s_\\)+\\)'")
- "Regexp matching doc string references to symbols.
-
-The words preceding the quoted symbol can be used in doc strings to
-distinguish references to variables, functions and symbols.")
-
-(defvar help-xref-info-regexp
- "\\<info\\s-+node\\s-`\\([^']+\\)'"
- "Regexp matching doc string references to an Info node.")
-
-(defun help-setup-xref (item interactive-p)
- "Invoked from commands using the \"*Help*\" buffer to install some xref info.
-
-ITEM is a (FUNCTION . ARGS) pair appropriate for recreating the help
-buffer after following a reference. INTERACTIVE-P is non-nil if the
-calling command was invoked interactively. In this case the stack of
-items for help buffer \"back\" buttons is cleared."
- (if interactive-p
- (setq help-xref-stack nil))
- (setq help-xref-stack-item item))
-
-(defun help-make-xrefs (&optional buffer)
- "Parse and hyperlink documentation cross-references in the given BUFFER.
-
-Find cross-reference information in a buffer and, if
-`help-highlight-p' is non-nil, highlight it with face defined by
-`help-highlight-face'; activate such cross references for selection
-with `help-follow'. Cross-references have the canonical form `...'
-and the type of reference may be disambiguated by the preceding
-word(s) used in `help-xref-symbol-regexp'.
-
-A special reference `back' is made to return back through a stack of
-help buffers. Variable `help-back-label' specifies the text for
-that."
- (interactive "b")
+(defun describe-key-briefly (key &optional insert)
+ "Print the name of the function KEY invokes. KEY is a string.
+If INSERT (the prefix arg) is non-nil, insert the message in the buffer."
+ (interactive "kDescribe key briefly: \nP")
(save-excursion
- (set-buffer (or buffer (current-buffer)))
- (goto-char (point-min))
- ;; Skip the header-type info, though it might be useful to parse
- ;; it at some stage (e.g. "function in `library'").
- (forward-paragraph)
- (let ((old-modified (buffer-modified-p)))
- (let ((stab (syntax-table))
- (case-fold-search t)
- (inhibit-read-only t))
- (set-syntax-table emacs-lisp-mode-syntax-table)
- ;; The following should probably be abstracted out.
- (unwind-protect
- (progn
- ;; Quoted symbols
- (save-excursion
- (while (re-search-forward help-xref-symbol-regexp nil t)
- (let* ((data (match-string 6))
- (sym (intern-soft data)))
- (if sym
- (cond
- ((match-string 3) ; `variable' &c
- (and (boundp sym) ; `variable' doesn't ensure
- ; it's actually bound
- (help-xref-button 6 #'describe-variable sym)))
- ((match-string 4) ; `function' &c
- (and (fboundp sym) ; similarly
- (help-xref-button 6 #'describe-function sym)))
- ((match-string 5)) ; nothing for symbol
- ((and (boundp sym) (fboundp sym))
- ;; We can't intuit whether to use the
- ;; variable or function doc -- supply both.
- (help-xref-button 6 #'help-xref-interned sym))
- ((boundp sym)
- (help-xref-button 6 #'describe-variable sym))
- ((fboundp sym)
- (help-xref-button 6 #'describe-function sym)))))))
- ;; Info references
- (save-excursion
- (while (re-search-forward help-xref-info-regexp nil t)
- (help-xref-button 1 #'info (match-string 1))))
- ;; An obvious case of a key substitution:
- (save-excursion
- (while (re-search-forward
- "\\<M-x\\s-+\\(\\sw\\(\\sw\\|\\s_\\)+\\)" nil t)
- (let ((sym (intern-soft (match-string 1))))
- (if (fboundp sym)
- (help-xref-button 1 #'describe-function sym)))))
- ;; Look for commands in whole keymap substitutions:
- (save-excursion
- ;; Make sure to find the first keymap.
- (goto-char (point-min))
- ;; Find a header and the column at which the command
- ;; name will be found.
- (while (re-search-forward "^key +binding\n\\(-+ +\\)-+\n\n"
- nil t)
- (let ((col (- (match-end 1) (match-beginning 1))))
- (while
- ;; Ignore single blank lines in table, but not
- ;; double ones, which should terminate it.
- (and (looking-at "^\n?[^\n]")
- (progn
- (if (and (> (move-to-column col) 0)
- (looking-at "\\(\\sw\\|\\s_\\)+$"))
- ;;
- (let ((sym (intern-soft (match-string 0))))
- (if (fboundp sym)
- (help-xref-button
- 0 #'describe-function sym))))
- t)
- (zerop (forward-line))
- (move-to-column 0)))))))
- (set-syntax-table stab))
- ;; Make a back-reference in this buffer if appropriate.
- (when help-xref-stack
- (goto-char (point-max))
- (save-excursion
- (insert "\n\n" help-back-label))
- ;; Just to provide the match data:
- (looking-at (concat "\n\n\\(" (regexp-quote help-back-label) "\\)"))
- (help-xref-button 1 #'help-xref-go-back (current-buffer))))
- ;; View mode steals RET from us.
- (set (make-local-variable 'minor-mode-overriding-map-alist)
- (list (cons 'view-mode
- (let ((map (make-sparse-keymap)))
- (set-keymap-parent map view-mode-map)
- (define-key map "\r" 'help-follow)
- map))))
- (set-buffer-modified-p old-modified))))
-
-(defun help-xref-button (match-number function data)
- "Make a hyperlink for cross-reference text previously matched.
-
-MATCH-NUMBER is the subexpression of interest in the last matched
-regexp. FUNCTION is a function to invoke when the button is
-activated, applied to DATA. DATA may be a single value or a list.
-See `help-make-xrefs'."
- ;; Don't mung properties we've added specially in some instances.
- (unless (get-text-property (match-beginning match-number) 'help-xref)
- (add-text-properties (match-beginning match-number)
- (match-end match-number)
- (list 'mouse-face 'highlight
- 'help-xref (cons function
- (if (listp data)
- data
- (list data)))))
- (if help-highlight-p
- (put-text-property (match-beginning match-number)
- (match-end match-number)
- 'face help-highlight-face))))
+ (let ((modifiers (event-modifiers (aref key 0)))
+ (standard-output (if insert (current-buffer) t))
+ window position)
+ ;; For a mouse button event, go to the button it applies to
+ ;; to get the right key bindings. And go to the right place
+ ;; in case the keymap depends on where you clicked.
+ (if (or (memq 'click modifiers) (memq 'down modifiers)
+ (memq 'drag modifiers))
+ (setq window (posn-window (event-start (aref key 0)))
+ position (posn-point (event-start (aref key 0)))))
+ (if (windowp window)
+ (progn
+ (set-buffer (window-buffer window))
+ (goto-char position)))
+ ;; Ok, now look up the key and name the command.
+ (let ((defn (or (string-key-binding key)
+ (key-binding key)))
+ (key-desc (key-description key)))
+ (if (or (null defn) (integerp defn))
+ (princ (format "%s is undefined" key-desc))
+ (princ (format (if insert
+ "`%s' (`%s')"
+ (if (windowp window)
+ "%s at that spot runs the command %s"
+ "%s runs the command %s"))
+ key-desc
+ (if (symbolp defn) defn (prin1-to-string defn)))))))))
-\f
-;; Additional functions for (re-)creating types of help buffers.
-(defun help-xref-interned (symbol)
- "Follow a hyperlink which appeared to be an arbitrary interned SYMBOL.
-
-Both variable and function documentation are extracted into a single
-help buffer."
- (let ((fdoc (describe-function symbol)))
- (describe-variable symbol)
- ;; We now have a help buffer on the variable. Insert the function
- ;; text after it.
- (goto-char (point-max))
- (let ((inhibit-read-only t))
- (insert "\n\n" fdoc)))
- (goto-char (point-min))
- (help-setup-xref (list #'help-xref-interned symbol) nil))
-
-(defun help-xref-mode (buffer)
- "Do a `describe-mode' for the specified BUFFER."
+
+(defun describe-key (key)
+ "Display documentation of the function invoked by KEY. KEY is a string."
+ (interactive "kDescribe key: ")
(save-excursion
- (set-buffer buffer)
- (describe-mode)))
+ (let ((modifiers (event-modifiers (aref key 0)))
+ window position)
+ ;; For a mouse button event, go to the button it applies to
+ ;; to get the right key bindings. And go to the right place
+ ;; in case the keymap depends on where you clicked.
+ (if (or (memq 'click modifiers) (memq 'down modifiers)
+ (memq 'drag modifiers))
+ (setq window (posn-window (event-start (aref key 0)))
+ position (posn-point (event-start (aref key 0)))))
+ (when (windowp window)
+ (set-buffer (window-buffer window))
+ (goto-char position))
+ (let ((defn (or (string-key-binding key) (key-binding key))))
+ (if (or (null defn) (integerp defn))
+ (message "%s is undefined" (key-description key))
+ (help-setup-xref (list #'describe-function defn) (interactive-p))
+ (with-output-to-temp-buffer (help-buffer)
+ (princ (key-description key))
+ (if (windowp window)
+ (princ " at that spot"))
+ (princ " runs the command ")
+ (prin1 defn)
+ (princ "\n which is ")
+ (describe-function-1 defn)
+ (print-help-return-message)))))))
+
\f
-;;; Navigation/hyperlinking with xrefs
-
-(defun help-follow-mouse (click)
- "Follow the cross-reference that you click on."
- (interactive "e")
- (let* ((start (event-start click))
- (window (car start))
- (pos (car (cdr start))))
- (with-current-buffer (window-buffer window)
- (help-follow pos))))
-
-(defun help-xref-go-back (buffer)
- "Go back to the previous help buffer text using info on `help-xref-stack'."
- (interactive)
- (let (item position method args)
- (with-current-buffer buffer
- (when help-xref-stack
- (setq help-xref-stack (cdr help-xref-stack)) ; due to help-follow
- (setq item (car help-xref-stack)
- position (car item)
- method (cadr item)
- args (cddr item))
- (setq help-xref-stack (cdr help-xref-stack))))
- (apply method args)
- (goto-char position)))
-
-(defun help-go-back ()
- (interactive)
- (help-follow (1- (point-max))))
-
-(defun help-follow (&optional pos)
- "Follow cross-reference at POS, defaulting to point.
-
-For the cross-reference format, see `help-make-xrefs'."
- (interactive "d")
- (let* ((help-data (or (and (not (= pos (point-max)))
- (get-text-property pos 'help-xref))
- (and (not (= pos (point-min)))
- (get-text-property (1- pos) 'help-xref))))
- (method (car help-data))
- (args (cdr help-data)))
- (setq help-xref-stack (cons (cons (point) help-xref-stack-item)
- help-xref-stack))
- (setq help-xref-stack-item nil)
- (when help-data
- ;; There is a reference at point. Follow it.
- (apply method args))))
-
-;; For tabbing through buffer.
-(defun help-next-ref ()
- "Find the next help cross-reference in the buffer."
- (interactive)
- (let (pos)
- (while (not pos)
- (if (get-text-property (point) 'help-xref) ; move off reference
- (goto-char (or (next-single-property-change (point) 'help-xref)
- (point))))
- (cond ((setq pos (next-single-property-change (point) 'help-xref))
- (if pos (goto-char pos)))
- ((bobp)
- (message "No cross references in the buffer.")
- (setq pos t))
- (t ; be circular
- (goto-char (point-min)))))))
-
-(defun help-previous-ref ()
- "Find the previous help cross-reference in the buffer."
+(defun describe-mode (&optional buffer)
+ "Display documentation of current major mode and minor modes.
+The major mode description comes first, followed by the minor modes,
+each on a separate page.
+For this to work correctly for a minor mode, the mode's indicator variable
+\(listed in `minor-mode-alist') must also be a function whose documentation
+describes the minor mode."
(interactive)
- (let (pos)
- (while (not pos)
- (if (get-text-property (point) 'help-xref) ; move off reference
- (goto-char (or (previous-single-property-change (point) 'help-xref)
- (point))))
- (cond ((setq pos (previous-single-property-change (point) 'help-xref))
- (if pos (goto-char pos)))
- ((bobp)
- (message "No cross references in the buffer.")
- (setq pos t))
- (t ; be circular
- (goto-char (point-max)))))))
+ (when buffer (set-buffer buffer))
+ (help-setup-xref (list #'describe-mode (current-buffer)) (interactive-p))
+ (with-output-to-temp-buffer (help-buffer)
+ (when minor-mode-alist
+ (princ "The major mode is described first.
+For minor modes, see following pages.\n\n"))
+ (princ mode-name)
+ (princ " mode:\n")
+ (princ (documentation major-mode))
+ (let ((minor-modes minor-mode-alist))
+ (while minor-modes
+ (let* ((minor-mode (car (car minor-modes)))
+ (indicator (car (cdr (car minor-modes)))))
+ ;; Document a minor mode if it is listed in minor-mode-alist,
+ ;; bound locally in this buffer, non-nil, and has a function
+ ;; definition.
+ (if (and (boundp minor-mode)
+ (symbol-value minor-mode)
+ (fboundp minor-mode))
+ (let ((pretty-minor-mode minor-mode))
+ (if (string-match "\\(-minor\\)?-mode\\'"
+ (symbol-name minor-mode))
+ (setq pretty-minor-mode
+ (capitalize
+ (substring (symbol-name minor-mode)
+ 0 (match-beginning 0)))))
+ (while (and indicator (symbolp indicator)
+ (boundp indicator)
+ (not (eq indicator (symbol-value indicator))))
+ (setq indicator (symbol-value indicator)))
+ (princ "\n\f\n")
+ (princ (format "%s minor mode (%s):\n"
+ pretty-minor-mode
+ (if indicator
+ (format "indicator%s" indicator)
+ "no indicator")))
+ (princ (documentation minor-mode)))))
+ (setq minor-modes (cdr minor-modes))))
+ (print-help-return-message)))
\f
;;; Automatic resizing of temporary buffers.
-(defcustom temp-buffer-resize-mode nil
- "Non-nil means resize windows displaying temporary buffers.
-This makes the window the right height for its contents, but never
-more than `temp-buffer-max-height' nor less than `window-min-height'.
-This applies to `help', `apropos' and `completion' buffers, and some others.
-
-This variable must be modified via \\[customize] in order to have an effect."
- :get (lambda (symbol)
- (and (memq 'resize-temp-buffer-window temp-buffer-show-hook) t))
- :set (lambda (symbol value)
- (temp-buffer-resize-mode (if value 1 -1)))
- :initialize 'custom-initialize-default
- :type 'boolean
- :group 'help
- :version "20.4")
-
(defcustom temp-buffer-max-height (lambda (buffer) (/ (- (frame-height) 2) 2))
"*Maximum height of a window displaying a temporary buffer.
This is the maximum height (in text lines) which `resize-temp-buffer-window'
:group 'help
:version "20.4")
-(defun temp-buffer-resize-mode (arg)
- "Toggle the mode which that makes windows smaller for temporary buffers.
+(define-minor-mode temp-buffer-resize-mode
+ "Toggle the mode which makes windows smaller for temporary buffers.
With prefix argument ARG, turn the resizing of windows displaying temporary
buffers on if ARG is positive or off otherwise.
-See the documentation of the variable `temp-buffer-resize-mode' for
-more information."
- (interactive "P")
- (let ((turn-it-on
- (if (null arg)
- (not (memq 'resize-temp-buffer-window temp-buffer-show-hook))
- (> (prefix-numeric-value arg) 0))))
- (if turn-it-on
- (progn
- ;; `help-mode-maybe' may add a `back' button and thus increase the
- ;; text size, so `resize-temp-buffer-window' must be run *after* it.
- (add-hook 'temp-buffer-show-hook 'resize-temp-buffer-window 'append)
- (setq temp-buffer-resize-mode t))
- (remove-hook 'temp-buffer-show-hook 'resize-temp-buffer-window)
- (setq temp-buffer-resize-mode nil))))
+This makes the window the right height for its contents, but never
+more than `temp-buffer-max-height' nor less than `window-min-height'.
+This applies to `help', `apropos' and `completion' buffers, and some others."
+ :global t :group 'help
+ (if temp-buffer-resize-mode
+ ;; `help-make-xrefs' may add a `back' button and thus increase the
+ ;; text size, so `resize-temp-buffer-window' must be run *after* it.
+ (add-hook 'temp-buffer-show-hook 'resize-temp-buffer-window 'append)
+ (remove-hook 'temp-buffer-show-hook 'resize-temp-buffer-window)))
(defun resize-temp-buffer-window ()
"Resize the current window to fit its contents.
Will not make it higher than `temp-buffer-max-height' nor smaller than
-`window-min-height'. Do nothing if it is the only window on its frame, if it
+`window-min-height'. Do nothing if it is the only window on its frame, if it
is not as wide as the frame or if some of the window's contents are scrolled
out of view."
(unless (or (one-window-p 'nomini)
(not (pos-visible-in-window-p (point-min)))
(/= (frame-width) (window-width)))
- (let* ((max-height (if (functionp temp-buffer-max-height)
- (funcall temp-buffer-max-height (current-buffer))
- temp-buffer-max-height))
- (win-height (1- (window-height)))
- (min-height (1- window-min-height))
- (text-height (window-buffer-height(selected-window)))
- (new-height (max (min text-height max-height) min-height)))
- (enlarge-window (- new-height win-height)))))
+ (fit-window-to-buffer
+ (selected-window)
+ (if (functionp temp-buffer-max-height)
+ (funcall temp-buffer-max-height (current-buffer))
+ temp-buffer-max-height))))
+
+;; Provide this for the sake of define-minor-mode which generates
+;; defcustoms which require 'help'.
+(provide 'help)
;;; help.el ends here